I learned that there is a language entirely based on whistling. Google Silbo Gomero. It’s a whistling language on the Canary Islands, a whistling dialect of Spanish. Quite a few residents there can communicate in it. A speaker of Silbo Gomero is called a ‘silbador’ (whistler). In 2009, the language was included in the List of the Intangible Cultural Heritage of Humanity. There are many videos about it on YouTube.
I started thinking about how humanity is rapidly losing the skill of whistling. Some can still whistle with their lips pursed, but with all other methods, it seems, no one can.
Apart from that, there is the palatal whistle (search for palatal whistle, roof of mouth whistle) — sharper and more piercing than the lip whistle, better at cutting through noise, but almost no change in pitch. There is also the rolled tongue whistle (search for rolled tongue whistle, taco tongue whistle) — low, dull, sounds like an owl, but reportedly, not everyone can do it (maybe genetics). With fingers in the mouth — louder (wash your hands!). Two fingers of one hand (index + middle or thumb + index ‘ring’) — 100-115 dB, up to 1 km in silence. This is precisely the basis of Silbo Gomero — pitch is adjusted by lip positioning and how deep the fingers are inserted, so much can be encoded. One finger (index or pinky hooked) — almost the same loudness, the other hand free. Fingers of both hands (one or two from each side) — the loudest manual whistle, up to 120 dB, across a valley 2-3 km in the mountains. Thumbs of both hands (nails to tongue) — loud, somewhat low, a tradition of shepherds in the Pyrenees, Caucasus, Balkans.
There’s also the whistle with cupped hands — low, 300-600 Hz, audible at 100-300 m, but the low sound bends around trees and bushes, so in the woods it travels further than a high sound. Pitch is changed by slightly opening the fingers, allowing for 5-8 notes to be whistled.
